Device, method and program product for data transmission management

ABSTRACT

The scanner  10  capable of functioning as a data transmission management device makes a judgment whether data should be allowed to be reused at a file transmission destination based on the nature of the particular destination, produces a reusable file, and transmits it to the destination, if it judges that the reuse of the data is allowed because the destination is within the area of the first network N 1  to which the scanner is connected; it produces a difficult-to-reuse file and transmits it to the destination, if it judges that the reuse of the data is disallowed because the destination is outside of the area of the first network

[0001] This application is based on Japanese Patent Application No. 2001-70882 filed on Mar. 13, 2001, the contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a device, a method and a program product for managing data transmission conducted via networks.

[0004] 2. Description of the Related Art

[0005] As the files for document display, files such as PDF (Portable Document Format) files, which include character code data that expresses characters as codes, image data that expresses images as an assembly of pixels, and vector data that expresses graphics as coordinates of components, each of which are objects that can be handled independently, are well known.

[0006] Files that consist of these objects have advantages that they can be easily edited and retrieved using character code data, that the quality of their output image is high, and that the total information of an original document can be maintained.

[0007] Consequently, those files containing multiple objects can also be reused, e.g., edited, altered, modified, and retrieved at transmission destinations when they are transmitted to other equipment through networks.

[0008] This causes a problem that they are vulnerable to fraudulent reuses or reuses against the will of the data producer at arbitrary transmission destinations, such as devices located outside of the network to which the sender's equipment is connected.

SUMMARY OF THE INVENTION

[0009] It is an object of the present invention to provide a device, a method and a program product for data transmission management, which are improved for solving the abovementioned problems.

[0010] It is a further object of the present invention to provide a device, a method and a program product for data transmission management capable of preventing the reuse of the data to be done fraudulently or against the will of the data producer at destinations of data transmission.

[0011] According to an aspect of the invention, it provides a data transmission management device for managing data transmission process via a network comprising: an input device for inputting data to be transmitted; a judgment means for judging whether reuse of data at a transmission destination should be approved in accordance with the nature of the particular destination of the data; and a data adjusting means for adjusting the data to be transmitted to the destination based on the result of the judgment either to be reusable or to be difficult-to-reused.

[0012] Therefore, it is capable of preventing the data from fraudulent reuses or from reuses against the will of the data producer, e.g., edited, altered, modified, and retrieved at transmission destinations when they are transmitted to arbitrary destinations such as devices located outside of the network to which the data transmitting source is connected.

[0013] According to another aspect of the invention, it provides a data transmission management method for managing data transmission process via a network comprising the steps of: obtaining data to be transmitted; judging whether reuse of data at a transmission destination should be approved in accordance with the nature of the particular destination of the data; and adjusting the data to be transmitted to the destination based on the result of the judgment either to be reusable or to be difficult-to-reused.

[0014] According to still another aspect of the invention, it provides a program product for managing data transmission process via a network, wherein the program product causes a computer to execute a process comprising the steps of: obtaining data to be transmitted; judging whether reuse of data at a transmission destination should be approved in accordance with the nature of the particular destination of the data; and adjusting the data to be transmitted to the destination based on the result of the judgment either to be reusable or to be difficult-to-reused.

[0015] According to still another aspect of the invention, it provides a data transmission management method for managing data transmission process via a network comprising the steps of: obtaining data to be transmitted; judging whether the data's transmission destination exists within a specified range of a network to which the destination belongs; and producing data to be transmitted to the destination either data consisting of multiple kinds of codes or data consisting of a single kind of code based on the judgment result.

[0016] The objects, features, and characteristics of this invention other than those set forth above will become apparent from the description given herein below with reference to preferred embodiments illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017]FIG. 1 is a diagram showing the constitution of a data transmission system including a data transmission management device according to the first embodiment of the present invention;

[0018]FIG. 2 is a block diagram showing an example constitution of the scanner;

[0019]FIG. 3 is a block diagram showing an example constitution of the computers;

[0020]FIG. 4 is a block diagram showing an example constitution of the mail servers;

[0021]FIG. 5 is a block diagram showing an example constitution of the relaying device;

[0022]FIG. 6 is a flowchart for describing the operation of the scanner;

[0023]FIG. 7 is a flowchart for describing the steps of producing a reusable file;

[0024]FIG. 8 is a flowchart for describing the steps of producing a file that is difficult to reuse;

[0025]FIG. 9 shows an example area judgment table;

[0026]FIG. 10 shows an example document;

[0027]FIG. 11 shows an example reusable file;

[0028]FIG. 12 shows an example content of the link information section;

[0029]FIG. 13 shows an example file that is difficult to reuse;

[0030]FIG. 14 is a flowchart showing the operation of a mail server capable of functioning as a data transmission management device according to the second embodiment of the present invention; and

[0031]FIG. 15 is a flowchart showing the operation of the relaying device capable of functioning as a data transmission management device according to the third embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0032] The embodiments of this invention will be described below with reference to the accompanying drawings.

[0033]FIG. 1 is a diagram showing the constitution of a data transmission system including a data transmission management device according to the first embodiment of the present invention.

[0034] The data transmission system shown in FIG. 1 includes a scanner 10, which functions as a data transmission device, personal computers (hereinafter simply called “computers”) 31 through 33, mail servers 51 and 52, and a relaying device 70.

[0035] The scanner 10, the computers 31 and 32, and the mail server 51 are connected to the first network N1, while the computer 33 and the mail server 52 are connected to the second network N2. There laying device 70 connects the first network N1 and the second network N2 to each other. The user of the computer 31 is A, the user of the computer 32 is B, and the user of the computer 33 is C.

[0036] The scanner 10, the computers 31 through 33, the mail servers 51 and 52 are constituted in such a way as to be able to communicate with each other via the networks N1 and N2 as well as the relaying device 70. The image data file obtained by scanning a document by the scanner can be transmitted to the computers, etc., as an attachment of electronic mail (e-mail). The number of networks, and the type and number of units of devices on the networks are not limited in actuality to those shown on FIG. 1.

[0037] The relaying device 70 is preferably a gateway capable of changing protocols. The networks N1 and N2 are, for example, LANs such as EthernetR, Token Ring, and FDDI (fiber distributed data interface), or WANs consisting of interconnected LANs. The difference in protocols between the first and second networks, N1 and N2, are immaterial.

[0038] Next, the constitutions of these devices will be described below.

[0039]FIG. 2 is a block diagram showing an example constitution of the scanner.

[0040] In FIG. 2, the scanner 10 has a control unit 11, a memory unit 12, an image-scanning unit 13, an operating panel 14, and a network interface 15.

[0041] The control unit 11 is in charge of executing the program, performing arithmetic operation, controlling various units, etc. The memory unit 12 stores various programs for controlling processes such as document scanning and data transmission as well as various data such as image data, storing the data temporarily as a working area for executing various processes. The memory unit 12 includes, for example, a stationary memory and a hard disk.

[0042] The image-scanning unit 13 obtains image data by scanning documents. The image data outputted from the image-scanning unit 13 is temporarily written into the memory and then transferred from the memory to the hard disk normally after completing one page of scanning to be stored in it.

[0043] The operating panel 14 includes, for example, an operating unit for the user to perform various operations and instructions, and a display unit for various displays.

[0044] The network interface 15 is an interface for the scanner 10 to communicate with other equipment via the first and second networks N1 and N2.

[0045]FIG. 3 is a block diagram showing an example constitution of the computers.

[0046] In FIG. 3, each of the computers 31 through 33 has a control unit 41, a memory unit 42, an input device 43, a display 44, and a network interface 45.

[0047] The control unit 41 is in charge of executing the program, performing arithmetic operation, controlling various units, etc. The memory unit 42 stores various programs and various data such as image data, storing the data temporarily as a working area for executing various processes. The memory unit 42 includes, for example, a stationary memory and a hard disk.

[0048] The input device 43 is an unit for the user to perform various operations and instructions, and specifically includes a keyboard, a mouse, etc. The display 44 is for displaying information. The network interface 45 is an interface for the computers 31 through 33 to communicate with other equipment via the first and second networks N1 and N2.

[0049]FIG. 4 is a block diagram showing an example constitution of the mail servers.

[0050] In FIG. 4, each of the mail servers 51 and 52 has a control unit 61, a memory unit 62, and a network interface 63. Furthermore, the servers 51 and 52 can be equipped each with an input device and a display as well.

[0051] The control unit 61 is in charge of executing the program, performing arithmetic operation, controlling various units, etc. The memory unit 62 stores various programs for controlling the processes such as sending and receiving e-mail via the networks as well as various data such as image data, storing the data temporarily as a working area for executing various processes. The memory unit 62 includes, for example, a stationary memory and a hard disk. The memory unit 62 includes mailboxes assigned to mail accounts respectively for storing e-mail.

[0052] The network interface 63 is an interface for the mail servers 51 and 52 to communicate with other equipment via the first and second networks N1 and N2.

[0053]FIG. 5 is a block diagram showing an example constitution of the relaying device.

[0054] In FIG. 5, the relaying device 70 has a control unit 81, a memory unit 82, a first network interface 83, and a second network interface 84. Furthermore, the relaying device 70 can be equipped each with an input device and a display as well.

[0055] The control unit 81 is in charge of executing the program, performing arithmetic operation, controlling various units, etc. The memory unit 82 stores various programs for controlling processes such as data transfer as well as various data such as image data, storing the data temporarily as a working area for executing various processes. The memory unit 82 includes, for example, a stationary memory and a hard disk.

[0056] The first network interface 83 is for connecting the relaying device 70 with the first network N1, and the second network interface 84 is for connecting the relaying device 70 with the second network N2.

[0057] Next, the operation of the scanner 10 will be described with reference to FIG. 6 through FIG. 8. The flowcharts shown in FIG. 6 through FIG. 8 are stored in the memory unit 12 of the scanner 10 as control programs, and are executed by the control unit 11.

[0058] As shown in FIG. 6, in the step S110, the scanner 10 receives various setup inputs from the user via the operating panel 14. In other words, the user can set up using the operating panel 14 various items such as scanning condition for document scanning and scanning data information. The contents set up here are stored into the memory unit 12.

[0059] The scanning condition includes scanning resolution, color/monochromatic selection, scaling factor, and scan size. The scanning data information includes data transmission destination, sender of the data, file name for registration, file's storage period, and confidentiality level.

[0060] In the step S120, the scanner 10 stands by until the scanning start instruction is received from the user via the operating panel 14; upon receiving the scanning instruction, the process of the step S130 is executed.

[0061] In this embodiment, a judgment is made in the step S130 depending on the data transmission destination whether it should be allowed to reuse the data at the transmission destination. The judgment is based on whether the data transmission destination set up in the step S110 is outside the area of the first network N1 to which the scanner 10 is connected. In other words, the approval for the data's reuse hinges upon whether the transmission destination is outside of its own network as viewed from the scanner 10.

[0062] If the transmission destination is within the first network N1, in other words, if it is either the user A or the user B (step S310: No), the process of the step S140 is executed; if the transmission destination is outside of the first network N1, in other words, if it is the user C (step S310: Yes), the process of the step S150 is executed. The order of execution of the step S120 and the step S130 can be reversed. It is also possible to accept only the setup input of the data transmission destination in the step S110, and accept the input of other setup items after processing the step S130.

[0063] A judgment whether the destination is outside the area of the first network N1 can be made, for example, referencing the area judgment table shown in FIG. 9. The area judgment table 90 consists of an address column 91 and a reuse approval information column 92. A portion of the destination's e-mail address is set up in the address column 91. In the reuse approval column 92, a data “1” is set if the reuse is approved, or a data “0” is set if the reuse is disapproved. The manager does the setup of each column of the area judgment table 90. In case of FIG. 9, the destination is judged to be in the area of the first network N1 and the reuse of the data at the destination is approved, if the e-mail address of the destination contains @000.co.jp. Also, the destination is judged to be outside of the area of the first network N1 and the reuse of the data at the destination is disapproved, if the e-mail address of the destination contains @111.co.jp. In other words, if the domain names of the e-mail addresses of the sender and the receiver of the data match with each other, it is judged that the data reuse at the destination is approved. In the current case, the e-mail addresses of the users A and B contain @000, .co.jp, and the e-mail address of the user C contains @111.co.jp.

[0064] The judgment whether reuse of the data at the destination is approved can be made not only using e-mail addresses, but also using various addresses such as IP addresses and MAC addresses, domain names, or various identification codes such as ID. Moreover, if IP addresses are to be used for judging whether reuse of the data at the destination is approved, for example, it can be done by judging whether a portion of an IP address, i.e., a portion of the IP address sectioned off at a certain position is included. Thus it is possible to preset the approval of the data reuse based on company, division, floor, department, group, or individual equipment.

[0065] In the step S140, reusable files are produced. The production of reusable files will be described below with reference to FIG. 7.

[0066] As shown in FIG. 7, document scanning is performed in the step S141. FIG. 10 shows an example document. The document 100 shown in FIG. 10 consists of a character section 101 where characters exist, a photograph section 102 where photographs exist, and a graphic section 103 where non-character graphics such as charts and graphs exist.

[0067] The scanning process starts when the user operates, for example, a start key of the operating panel 14. The image-scanning unit 13 scans the first page of the document set at the specified position of the scanner 10, consequently obtaining image data, which expresses images as an assembly of pixels. The obtained image data is stored in the memory unit 12.

[0068] In the step S142, an area separation process is performed on the obtained image. The image data is separated into a character area that corresponds to the character section 101 where character images exist, a photographic area that corresponds to the photograph section 102 where photographic images exist, and a graphic area that corresponds to the graphic section 103 where graphic images exist. Moreover, location information (layout information) that shows the location of each area on the output image, e.g., the coordinates of the left top corner and the right bottom corner of a rectangle that circumscribes each area, is detected in this process. Furthermore, an image correction process is performed for each area in accordance with its attribute.

[0069] In the step S143, image process for each area is performed respectively. In other words, character codes are recognized from character images within the character area, and character code data is generated that expresses characters as codes in response to the recognized characters. Photographic images in the photographic area are converted into image data of appropriate resolution and applied a compression process to be generated as photographic image data that expresses photographs as an assembly of pixels. The appropriate resolution here means relatively low resolution that dose not make the amount of data transmitted too large. The reason for converting only photo graphic images to appropriate resolution after area separation is because there are character images and graphic images that require higher resolution than photographic images in the document. Graphic images in the graphic area are converted into vector data that expresses graphics as the coordinates of their components.

[0070] In the step S144, the character code data, the photographic image data, and the vector data generated in the step S143 are synthesized and stored in the memory unit 12. Moreover, each data, layout information indicating the location of each data on the output image, and link information indicating the location of each data within the synthesized data are stored into the memory unit 12.

[0071] In the step S145, a judgment is made whether the next page of the document exists. If there is another page at the specified position of the scanner 10 (step S145: Yes), it returns to the step S141 and repeats the processes of the step S141 through the step S145. If no document is left at the specified position of the scanner 10 (step S145: No), the process of the step S146 is executed.

[0072] In the step S146, the data stored in the memory unit 12 in the abovementioned step is read out and converted into a reusable file of a specified format. This reusable file is a file that contains character code data, image data, and vector data as objects that can be handled individually. Therefore, it is possible to reuse the file performing editing, alteration, modification and retrieval. Moreover, although the file to be converted is, for example, a PDF (portable document format) file, it is not limited to it and can be any existing files such as an HTML (hypertext markup language) file and an XML (extensible markup language) file, or a file of a proprietary format.

[0073]FIG. 11 shows an example reusable file produced in the step S146. The reusable file 200 shown in FIG. 11 includes a header section 201, a layout information section 202, a link information section 203, a character code data section 204, a photographic image data section 205, a vector data section 206, a total image data section 207, and a file end section 208.

[0074] The header section 201 stores data such as the format and size (volume) of the particular file 200. The layout information section 202 stores layout information that shows the location of each object of character code data, photographic image data, and vector data on the output image. The link information section 203 stores link information that shows the location of each object within the file.

[0075] The character code data section 204, the photographic image data section 205, the vector data section 206, and the total image data section 207 store the character code data that correspond to the character section 101, the photographic image data that correspond to the photographic section 102, the vector data that correspond to the graphic section 103, and the image data that correspond to the entire document 100 respectively when the document 100 shown in FIG. 10, for example, is scanned.

[0076] The reusable files in this invention can be, for example, files containing the data consisting only of character code data and total image data. Furthermore, the reusable files can be files containing the data consisting only of character code data, or of character code data and vector data.

[0077]FIG. 12 shows an example content of the link information section 203. In FIG. 12, “Object101” is a code that represents the character code data as an object, and shows that the object is stored starting from the 100^(th) address of the file. Similarly, “Object102,” “Object103,” and “Object104” are codes that represent the photographic image data, vector data, and total image data respectively as objects, and show that they are located starting from the 200^(th,) 300^(th), and 400^(th) address of the file.

[0078] In the step S147, the reusable file 200 prepared at the step S146 is transmitted to the specified destination attached to an e-mail. The e-mail attached with the file is stored in the mailbox of the user according to the destination of the e-mail, located in the memory unit 62 of the mail server 51. However, the file 200 can be transmitted to a specific destination according to a specified transfer protocol without relying on e-mail.

[0079] On the other hand, in the step S150 shown in FIG. 6, the files that are difficult to reuse are prepared. The procedure for producing difficult-to-reuse files will be described with reference to FIG. 8.

[0080] As shown in FIG. 8, the document scanning is done in the step S151 same as in the step S141 shown in FIG. 7. In other words, the document image is obtained as the first page of the document set at the specified position of the scanner 10. The obtained image data is stored in the memory unit 12.

[0081] In the step S152, a judgment is made whether the next page of the document exists. If there is another page at the specified position of the scanner 10 (step S152: Yes), it returns to the step S151 and repeats the document scanning process. If no document is left at the specified position of the scanner 10 (step S152: No), the process of the step S153 is executed.

[0082] In the step S153, the data stored in the memory unit 12 in the step S151 is read out and converted into a difficult-to-reuse file of a specified format. This difficult-to-reuse file is a file that contains data that consist only of the image data that expresses images as an assembly of pixels. Therefore, it is difficult to reuse the file performing editing, alteration, modification and retrieval. Moreover, although the file to be converted is, for example, a PDF file that does not contain any data other than image data, for example, character code data, it is not limited to it and can be any existing files such as a BMP (bitmap) file and a JPEG (joint photographic experts) file, or a file of a proprietary format.

[0083]FIG. 13 shows an example of such a difficult-to-reuse file prepared in the step S153. The difficult-to-reuse file 300 shown in FIG. 13 is different from the reusable file 200 shown in FIG. 11 in the sense that it stores no data in either the character code section 204, the photographic image data section 205, or the vector data section 206, but is the same in other aspects so that its details descriptions are omitted here.

[0084] In the step S154, the difficult-to-reuse file 300 prepared in the step S153 is transmitted to a specified destination attached to an e-mail. The e-mail message attached with the file is stored in the mailbox of the user according to the destination of the e-mail, located in the mail server 52. However, this file 300 can be transmitted to a specific destination according to a specified transfer protocol without relying on e-mail.

[0085] As can be seen from the above, scanner 10 according to this embodiment makes a judgment on whether to allow the reuse of a data at a transmission destination depending on the nature such as address information of the particular destination. When it determines that the destination is within the area of the first network N1, to which the scanner 10 is connected, so that the reuse of the data at the destination is allowed, it produces a reusable file 200 and transmits it to the particular destination; on the contrary, if it determines that the destination is outside of the area of the first network N1, so that it is not allowed to reuse the data at the destination, it produces a difficult-to-reuse file 300 and transmits it to the particular destination.

[0086] Consequently, it is capable of preventing a file from being fraudulently, or against the will of the file producer, edited, altered, modified, and retrieved at arbitrary transmission destinations such as equipment provided outside of the area of the network N1, to which the data transmitting source, the scanner 10, is connected.

[0087]FIG. 14 is a flowchart showing the operation of a mail server capable of functioning as a data transmission management device concerning the second embodiment of the present invention. The flowchart shown in FIG. 14 is stored in the memory unit 62 of the mail server 51 as a control program and is executed by the control unit 61.

[0088] The second embodiment of the invention is different in that its mail server 51 is capable of functioning as the data transmission management device from the first embodiment, in which its scanner 10 is capable of functioning as the data transmission management device. Mainly the differences between the first and second embodiments will be described and the commonality will be omitted in the following.

[0089] The description will be about a case of transmitting an e-mail attached with a file transmitted from the user A to the user B or the user C.

[0090] As shown in FIG. 14, an e-mail attached with a file transmitted is received from the user A in the step S201.

[0091] In the step S202, a judgment is first made on whether to allow the reuse of the data at a transmission destination depending on the nature of the particular destination. What is judged here is whether the destination is within the area of the first network N1, to which the mail server 15 is connected, based on the address of the e-mail destination. In other words, the judgment whether the reuse of the data should be allowed is hinging upon the judgment on whether the destination is within the area of its own network from the viewpoint of the mail server 51. The above judgment can be made using a table similar to the area judgment table 90 of the first embodiment as well.

[0092] If the transmission destination is outside the area of the first network N1, for example, if it is the user C (step S202: Yes), the process of the step S203 is executed; if the destination is within the area of the first network N1, for example, if it is the user B (step S202: No), the process of the step S209 is executed.

[0093] In the step S203, the header section of the e-mail is analyzed. Since the analysis is normally done in an e-mail transmission process, detailed description is omitted.

[0094] In the step S204, a judgment is made whether any file is attached to the e-mail based on the result of the analysis in the step S203. If a file is attached to the e-mail (step S204: Yes), the process of the step S205 is executed; if no file is attached (step S204: Yes), the process of the step S209 is executed.

[0095] In the step S205, the header section of the file attached to the e-mail is analyzed. By analyzing the header section of the file, the format of the file (e.g., PDF) can be recognized.

[0096] In the step S206, a judgment is made whether the particular file is a reusable file based on the recognized file format as a result of the analysis in the step S205. More specifically, a judgment is made whether the file has character code data, image data, and vector data such as those shown in FIG. 11 as objects that can be handled individually. If a file attached to an e-mail is a reusable file (step S206: Yes), the process of the step S207 is executed; if it is not a reusable file (step S206: No), the process of the step S209 is executed.

[0097] In the step S207, reusable portions are detected from the file attached to an e-mal message. The file's link information is utilized for the detection. If the reusable file is, for example, the file 200 shown in FIG. 11, the character code data section 204, the photographic image data section 205, and the vector data section 206 are detected as reusable portions.

[0098] In the step S208, the data of the reusable portions detected in the step S207 are deleted. For example, in case of the file 200 shown in FIG. 11, the data of the character code data section 204, the photographic image data section 205, and the vector data section 206 are deleted. It is also possible reconstruct the file by deleting the character code data section 204, the photographic image data section 205, and the vector data section 206 themselves.

[0099] Consequently, the reusable file 200 is converted into the difficult-to-reuse file 300 shown in FIG. 13. Since the character code data stored in the character code data section 204 is the easiest to reuse, it is also possible to adopt the constitution that deletes only the data in the character code data section 204. Further, it is also possible to adopt the constitution that deletes only character code data from a file that has both character code data and image data, or deletes only vector data from a file that has both vector data and image data.

[0100] In the step S209, if the e-mail destination is the user C, the e-mail attached with a difficult-to-reuse file is transmitted, while if the e-mail destination is the user B, the received e-mail is transmitted as is to the user B's mailbox at the memory unit 62 of the mail server 51.

[0101] E-mail addressed to the user C is stored in the mailbox for the user C in the memory unit 62 of the mail server 52. E-mail to the user Band e-mail to the user C are distributed to the computer of each user from the mail servers 51 and 52 respectively.

[0102] As can be seen from the above, this embodiment causes the mail server 51 to make a judgment on whether to allow the reuse of data at an e-mail destination based on the nature of the particular destination of the e-mail. If it judges that the reuse of the data is allowed because the destination is within the area of the first network N1 to which the mail server 51 is connected, it transmits the e-mail as is to the particular destination; if it judges that the reuse of the data is not allowed because the destination is outside the area of the first network N1, it converts the attached file to a difficult-to-reuse file, and the e-mail attached with a converted file is transmitted to the particular destination.

[0103] Therefore, it is capable of preventing a file from being fraudulently, or against the will of the file producer, edited, altered, modified, and retrieved at arbitrary transmission destinations such as equipment provided outside of the area of the network N1, to which the mail server 51 is connected.

[0104] Although a constitution was described from the viewpoint of assuredness and ease of management for the second embodiment, in which the mail server that receives e-mail transmitted by the user has a capability of functioning as a data transmission management device, it is also possible to let the mail server that distributes e-mail to the user have the same function as the data transmission management device.

[0105]FIG. 15 is a flowchart showing the operation of the relaying device capable of functioning as a data transmission management device concerning the third embodiment of the present invention. The flowchart shown in FIG. 15 is stored in the memory 82 of the relaying device 70 as a control program and is executed by the control unit 81.

[0106] The third embodiment is different from the first embodiment in that the relaying device 70 is capable of functioning as a data transmission management device in the former, while the scanner 10 functions as a data transmission management device in the latter. Mainly the differences between the first and third embodiments will be described and the commonality will be omitted in the following.

[0107] A case of sending a file from the user A to the user B or to the user C will be described. The file transmission is executed according to the specified transfer protocol such as FTP (file transfer protocol).

[0108] As shown in FIG. 15, the file is received from the user A in the step S301.

[0109] In the step S302, a judgment is made on whether to allows the reuse of the data at a transmission destination based on the nature of the particular destination of the file. What is judged here is whether the destination is within the area of the first network N1, to which the computer 31 of the user A, who is the transmitting source, is connected, based on the address of the file destination. In other words, the judgment whether the reuse of the data should be allowed is hinging upon the judgment on whether the destination is within the area of its own network from the viewpoint of the computer 31 of the transmitting source. The above judgment can be made using a table similar to the area judgment table 90 of the first embodiment as well.

[0110] If the destination is outside the area of the first network N1, for example, if it is the user C (step S302: Yes), the process of the step S303 is executed; if the destination is within the area of the first network N1, for example, if it is the user B (step S302: No), the process of the step S307 is executed.

[0111] In the step S303, the header section of the file is analyzed. By analyzing the file's header section, the type of the file (e.g., PDF) can be recognized.

[0112] In the step S304, a judgment is made whether the file is a reusable file based on the recognized file format as the result of the analysis in the step S303. More specifically, a judgment is made whether the file has character code data, image data, and vector data such as those shown in FIG. 11 as objects that can be handled individually. If a file is a reusable file (step S304: Yes), the process of the step S305 is executed; if it is not a reusable file (step S304: No), the process of the step S307 is executed.

[0113] In the step S305, reusable portions are detected from the file. The file's link information is utilized for the detection. If the reusable file is, for example, the file 200 shown in FIG. 11, the character code data section 204, the photographic image data section 205, and the vector data section 206 are detected as reusable portions.

[0114] In the step S306, the data of the reusable portions detected in the step S305 are deleted. For example, in case of the file 200 shown in FIG. 11, the data of the character code data section 204, the photographic image data section 205, and the vector data section 206 are deleted. Moreover, it is possible to reconstruct the file by deleting the character code data section 204, the photographic image data section 205, and the vector data section 206 themselves.

[0115] Consequently, the reusable file 200 is converted into the difficult-to-reuse file 300 shown in FIG. 13. Since the character code data stored in the character code data section 204 is the easiest to reuse, it is also possible to adopt the constitution that deletes only the data in the character code data section 204. Further, it is also possible to adopt the constitution that deletes only character code data from a file that has both character code data and image data, or deletes only vector data from a file that has both vector data and image data.

[0116] In the step S307, if the file transmission destination is the computer 33 of the user C, a difficult-to-reuse file is transmitted, while if the file destination is the computer 32 of the user B, the received file is transmitted as is to the first network N1.

[0117] As can be seen from the above, this embodiment causes the relaying device 70 to make a judgment on whether to allow the reuse of data at a destination based on the nature of the particular destination of the file. If it judges that the reuse of the data is allowed because the destination is within the area of the first network N1 to which the computer 31 of the transmitting source is connected, it transmits the file as is to the particular destination; if it judges that the reuse of the data is not allowed because the destination is outside the area of the first network N1, it converts the file to a difficult-to-reuse file, and the converted file is transmitted to the particular destination.

[0118] Therefore, it is capable of preventing a file from being fraudulently, or against the will of the file producer, edited, altered, modified, and retrieved at arbitrary transmission destinations such as equipment provided outside of the area of the network N1, to which the computer 31 of the transmitting source is connected.

[0119] The invention is not limited to the embodiments described above, but rather can be modified in various ways within the scope of the claims.

[0120] For example, although the constitution was described in which the judgment allowing the reuse of the data at the destination is made based on whether the destination is on the first network N1 or the second network N2, the invention is not limited to such a constitution, but rather it can be constituted in such a way that there are more than three networks in the system and that the judgment allowing the reuse of the data at the destination is made based on whether the destination is on at least one of the specified network. It is also possible to constitute in such a way that the judgment allowing the reuse of the data at the destination is made based on whether the destination is a particular device identified by an address, etc., regardless of the network it belongs.

[0121] Moreover, although it was described as if the first through the third embodiments exist independent of each other in the above descriptions, the invention can be implemented by combining the first through the third embodiments arbitrarily.

[0122] Various means of controlling and arithmetic operations in the data transmission management device as well as data transmission management method according to this invention can be realized either by a dedicated hardware circuit or a programmed computer. In realizing the present invention with a programmed computer, the program for operating the computer can be provided in computer readable recording media (e.g., flexible disks and CD-ROMs). In such a case, the program recorded on a computer readable medium is normally transferred to and recorded on a hard disk. This program can be provided, for example, independently as application software, or can be built into the software of the computer as a part of the computer's function. The computer program product in this invention includes the computer program itself as well as the computer readable recording media on which the computer program is stored. 

What is claimed is:
 1. A data transmission management device for managing data transmission process via a network comprising: an input device for inputting data to be transmitted; a judgment means for judging whether reuse of data at a transmission destination should be approved in accordance with the nature of the particular destination of said data; and a data adjusting means for adjusting the data to be transmitted to said destination based on the result of said judgment either to be reusable or to be difficult-to-reused.
 2. A data transmission management device as claimed in claim 1, wherein said judgment means judges that the reuse of the data at said transmission destination is approved if the domain name of e-mail address of the transmission source matches with that of the transmission destination of the data.
 3. A data transmission management device as claimed in claim 1, wherein said judgment means judges that the reuse of the data at said transmission destination is approved if a specified part of the IP address of the transmission source matches with that of the transmission destination of the data.
 4. A data transmission management device as claimed in claim 1, wherein said input device is an image reading device for obtaining image data where images are expressed as an assembly of pixels by scanning a document.
 5. A data transmission management device as claimed in claim 4, further comprising: a character code data producing means for producing character code data where characters are expressed as codes based on character images in said image data, wherein said data adjusting means produces a file that has data containing said character code data if it is judged by said judgment means that the reuse of the data at the transmission destination is approved, while it produces a file that has data consisting only of said image data if it is judged by said judgment means that the reuse of the data at the transmission destination is disapproved.
 6. A data transmission management device as claimed in claim 5, further comprising: a vector data producing means for producing vector data where graphics are expressed as coordinates of graphic components based on graphic images in said image data, wherein said data adjustment means produces a file that has data containing said character code data and said vector data if it is judged by said judgment means that the reuse of the data at the transmission destination is approved, while it produces a file that has data consisting only of said image data if it is judged by said judgment means that the reuse of the data at the transmission destination is disapproved.
 7. A data transmission management device as claimed in claim 1, wherein said data is a file having a character code data where characters are expressed as codes, and an image data where images are expressed in an assembly of pixels, each as objects that can be handled independently, wherein said data adjusting means is capable of deleting said character code data from said file if it is judged by said judgment means that the reuse of the data at the transmission destination is disapproved.
 8. A data transmission management device as claimed in claim 1, wherein said data is a file having a vector data where graphics are expressed as coordinates of graphic components, and an image data where images are expressed in an assembly of pixels, each as objects that can be handled independently, wherein said data adjusting means is capable of deleting said vector data from said file if it is judged by said judgment means that the reuse of the data at the transmission destination is disapproved.
 9. A data transmission management device as claimed in claim 1, wherein said input device is a network interface for obtaining image data via a network.
 10. A data transmission management method for managing data transmission process via a network comprising the steps of: obtaining data to be transmitted; judging whether reuse of data at a transmission destination should be approved in accordance with the nature of the particular destination of said data; and adjusting the data to be transmitted to said destination based on the result of said judgment either to be reusable or to be difficult-to-reused.
 11. A program product for managing data transmission process via a network, wherein said program product causes a computer to execute a process comprising the steps of: obtaining data to be transmitted; judging whether reuse of data at a transmission destination should be approved in accordance with the nature of the particular destination of said data; and adjusting the data to be transmitted to said destination based on the result of said judgment either to be reusable or to be difficult-to-reused.
 12. A program product as claimed in claim 11, wherein said program product is a computer program.
 13. A program product as claimed in claim 11, wherein said program product is a computer readable recording medium on which the computer program is stored.
 14. A data transmission management method for managing data transmission process via a network comprising the steps of: obtaining data to be transmitted; judging whether said data's transmission destination exists within a specified range of a network to which the destination belongs; and producing data to be transmitted to said destination either data consisting of multiple kinds of codes or data consisting of a single kind of code based on said judgment result.
 15. A data transmission management device for managing data transmission process via a network comprising: an input device for inputting data to be transmitted; and a controller for judging whether reuse of data at a transmission destination should be approved in accordance with the nature of the particular destination of said data, and for adjusting the data to be transmitted to said destination based on the result of said judgment either to be reusable or to be difficult-to-reused. 